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| 1 | |
Which of the following is not a result of gene regulation? |
| | A) | Cell differentiation |
| | B) | One gene : many proteins |
| | C) | DNA methylation |
| | D) | Negative control |
| | E) | All of the choices result from gene regulation. |
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| 2 | |
In bacteria, transcriptional regulation by ________ proteins is called ________ control. |
| | A) | repressor; negative |
| | B) | activator; negative |
| | C) | repressor; positive |
| | D) | small; micro |
| | E) | constitutive; feedback |
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| 3 | |
Which of the following contributes to the combinatorial control of eukaryotic gene expression? |
| | A) | activator proteins |
| | B) | repressor proteins |
| | C) | effector molecules |
| | D) | DNA methylation |
| | E) | All of the choices contribute to combinatorial control in eukaryotes. |
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| 4 | |
True or False: A core promoter is able to produce low level basal transcription by itself. |
| | A) | True |
| | B) | False |
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| 5 | |
Which of the following is not an example of genetic regulation? |
| | A) | E. coli decreases expression of beta-galactosidase in response to lactose in the growth medium. |
| | B) | The cells in a developing fetus synthesize the same proteins in each stage of development. |
| | C) | Brain cells produce a different set of proteins than muscle cells. |
| | D) | A cell has encountered DNA damage and expresses a set of repair RNA molecules to fix the damage. |
| | E) | E. coli produces a polycistronic mRNA molecule from the lac operon in response to the presence of glucose in its surrounding environment. |
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| 6 | |
At which of the following steps do eukaryotes perform genetic regulation?
I: Transcription
II: Translation
III: mRNA processing
VI: Protein synthesis
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| | A) | i, ii, iii |
| | B) | iii, iv |
| | C) | ii, iii, iv |
| | D) | i, ii, iii, iv |
| | E) | ii, iv |
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| 7 | |
At which of the following steps do bacteria most frequently perform genetic regulation? |
| | A) | RNA Processing |
| | B) | Transcription |
| | C) | mRNA Processing |
| | D) | Protein synthesis |
| | E) | Bacteria perform genetic regulation equally at all of the steps listed. |
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| 8 | |
True or False: A single molecule of mRNA that has coding sequences for more than one structural protein is called polycistronic. |
| | A) | True |
| | B) | False |
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| 9 | |
Which of the following statements about lactose regulation in E. coli is incorrect? |
| | A) | The protein product of the lacY gene allows lactose to be taken up by the cell. |
| | B) | The binding of the lac repressor protein to the operator region is dependent on the presence of allolactose. |
| | C) | The lac operon is inducible. |
| | D) | The lacZ, lacY, lacA and lacI genes comprise the lac operon. |
| | E) | The protein product of the lacZ gene coverts lactose to glucose and galactose. |
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| 10 | |
The lac operator region is an example of a ________ and the product of the lacI gene is an example of a ________. |
| | A) | cis-acting element; cis-acting element |
| | B) | trans-acting element; trans-acting element |
| | C) | cis-acting element; trans-acting element |
| | D) | trans-acting element; cis-acting element |
| | E) | positive control ; negative control |
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| 11 | |
Under which of the following conditions would lac operon expression in E. coli be minimal? |
| | A) | High levels of glucose, low levels of lactose |
| | B) | Low levels of glucose, high levels of lactose |
| | C) | High levels of glucose, high levels of lactose |
| | D) | Low levels of glucose, low levels of lactose |
| | E) | lac operon expression is never minimized |
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| 12 | |
True or False: Tryptophan acts as an inducer of the trp operon by binding to the trp repressor protein, releasing it from the trp operator. |
| | A) | True |
| | B) | False |
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| 13 | |
Repressible operons are typically involved in ________ and inducible operons are typically involved in ________. |
| | A) | transcription; translation |
| | B) | eukaryotes; prokaryotes |
| | C) | prokaryotes; eukaryotes |
| | D) | catabolism; anabolism |
| | E) | anabolism; catabolism |
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| 14 | |
Which of the following would most likely be found in prokaryotes? |
| | A) | Generalized transcription factors |
| | B) | TATA box |
| | C) | Arrangement of structural genes in an operon |
| | D) | Mediator |
| | E) | All of the choices would equally likely be found in eukaryotes. |
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| 15 | |
Chromatin takes part in gene regulation through |
| | A) | closed conformation. |
| | B) | open conformation. |
| | C) | the location of nucleosomes. |
| | D) | closed conformation and open conformation. |
| | E) | closed conformation, open conformation, and the location of nucleosomes. |
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| 16 | |
Which of the following statements about the regulation of gene expression in eukaryotes is incorrect? |
| | A) | Chromatin in the closed conformation is more easily transcribed than chromatin in the open conformation. |
| | B) | Acetylated histones do not bind as tightly to DNA as non-acetylated histones. |
| | C) | ATP-dependent chromatin remodeling enzymes can be recruited to a site of transcription by activator proteins. |
| | D) | Steroid hormone receptor molecules often function as transcriptional activators. |
| | E) | All of these choices about the regulation of gene expression in eukaryotes are correct. |
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| 17 | |
True or False: Alternative splicing is a form of gene regulation that utilizes the same molecule of mRNA to produce different proteins? |
| | A) | True |
| | B) | False |
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| 18 | |
True or False: DNA methylation typically enhances the expression of a eukaryotic gene. |
| | A) | True |
| | B) | False |
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| 19 | |
Which one of the following statements about alternative splicing is correct? |
| | A) | Alternative splicing leads to different protein products with very different functions. |
| | B) | Alternative splicing enables an organism to increase the size of its genome without having to increase the size of its proteome. |
| | C) | Alternative splicing is common in all eukaryotes, but uncommon in prokaryotes. |
| | D) | Alternate forms of a protein are made by different cell types, or at different stages of development, from a single gene in the genome. |
| | E) | All of the choices about alternative splicing are correct. |
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| 20 | |
Which of the following statements about RNA interference is incorrect? |
| | A) | RNA interference is an example of genetic regulation at the level of transcription. |
| | B) | Precursor miRNAs form a hairpin loop and are then hydrolyzed by dicer. |
| | C) | MiRNAs associate with cellular proteins and then bind to target sequences in mRNA. |
| | D) | In animals, RISC inhibits translation. |
| | E) | In plants, RISC targets a mRNA for degradation. |
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